LCOE reduction potential of parabolic trough and solar tower CSP … SolarPACES... · 2016. 12. 1. · Technology-based bottom-up approach relying on inhouse expertise as well as

LCOE reduction potential of parabolic trough

and solar tower CSP technology until 2025

S. Dieckmann, J. Dersch, S. Giuliano, M. Puppe, E. Lüpfert, K. Hennecke, R. Pitz-Paal

(German Aerospace Center, DLR)

M. Taylor, P. Ralon

(International Renewable Energy Agency, IRENA)

SolarPACES Conference

Abu Dhabi

October 11-14, 2016

Content

> SolarPACES Conference > Oct 11-14, 2016 > Abu Dhabi > LCOE reduction of CSP until 2025 > Simon Dieckmann DLR.de • Chart 2

1. Introduction

2. System Overview 2015 vs. 2025

3. Cost Analysis

1. Parabolic Trough Field

2. Solar Tower System

3. Thermal Energy Storage

4. Power Block

4. Results

5. Conclusion

Source: noorouarzazate.com

1. Introduction – Contributing Cost Factors for LCOE

Example based on annuity

loan over 25 years at 7.5%

Main Impact factors:

Investment cost (CAPEX)

Financing conditions

LCOE estimation is mainly

CAPEX estimation


Loan repayment

37%

Interest 47%

Insurance 5%

O&M 11%

Electricity from grid

0.5%

1. Introduction – Methodology and Boundary Conditions


Technology-based bottom-up approach relying on inhouse

expertise as well as external data sources

Contrasted with published Power Purchase Agreements

(NOOR II + III)

Ouarzazate, Morocco, DNI: 2017 / 2558 / 2935 kWh/(m²∙a)

Currency: US-$2015

CSP capacity growth to about 20GW in 2025

Parabolic Trough Solar Tower

Nominal Electric Net Output 160 MW 150 MW

Thermal Storage Capacity 7.5 h 9 h

2. System Overview – Parabolic Trough 2015 2025


Solar Field Thermal Storage Power Block HTF System

Aperture width: 7.5m 10m

Molten salt as HTF

Tout = 393°C 530°C Thot = 385°C 530°C

Storage volume halved!

η = 37.4% 42.7%

Constant optical

efficiency (79.1%)

2. System Overview – Solar Tower 2015 2025


Heliostat Field Tower & Receiver Thermal Storage Power Block

Thot = 565°C 600°C η = 42.8% 43.9%

ρmirror = 89.3% 91.2%

Closed loop control

Optimized heliostat and field design

ηreceiver = 87.6% 90.5%

Higher acceptable flux

Enhanced thermo-hydraulic design

3.1 Cost and Performance – Parabolic Trough Field


Total cost reduction: 23%

Cost reduction equally distributed

over sub-components

25% less collectors, foundations,

pylons, drives and receivers

Collector structure: -14 $/m²

(Sub-)supplier standards and

standardized designs

Automatization in manufacturing

HTF cost: -18$/m²

2015 2025

Collector UltimateTrough™ Future Trough

Turnkey Cost* 231 $/m² 177 $/m²

*: includes site preparation, collectors, piping, cabling, HTF, HTF system, assembly & construction

Source: sbp.de

3.2 Cost and Performance – Solar Tower System

Total heliostat cost reduction: -28%

Mirrors: -9 $/m²

Reach parabolic trough mirror cost

Drives: -11 $/m²

Replace costly slewing drives

Closed loop control

Structure & foundations: - 10 $/m²

Bigger market volume, standardized designs

Idustrialized assembly procedures


Total receiver cost reduction: -20%

Improved material concepts

Optimized absorber surface utilization

Higher average solar flux

2015 2025

Heliostat Stellio™ Future Heliostat

Heliostat Field Cost* 143 $/m² 103 $/m²

Tower Cost 90,000 $/m 72,000 $/m

Receiver Cost 125 $/kWth 100 $/kWth

*: includes site preparation, heliostat field, cabling, assembly & construction

Source: sbp.de

3.3 Cost and Performance – Thermal Storage


Both technologies:

Adapted storage materials

Innovative storage concepts (e.g. Single-tank thermocline storage)

Tower Storage Costs: -4 $/kWh (-17%)

Trough Storage Costs: -16 $/kWh (-38%)

-12.5 $/kWh for storage medium

halved storage fluid mass thanks to higher temperature

-3 $/kWh for HXs and pumps

Source: www.renewableenergyfocus.com


2015 2025 2015 2025

Cost 42 26 26 22 $/kWh

Hot tank temperature 385 530 565 600 °C

3.4 Cost and Performance – Power Block


Minor cost reduction potential

Dry cooling predominant

Efficiency gain thanks to

increased live steam

temperatures

Source: The Energy Blog – energy.org.za


2015 2025 2015 2025

Cost 1220 1100 1270 1100 $/kW

Live Steam Temperature 383 520 555 590 °C

Thermal Efficiency 38.4 42.7 42.8 43.9 %

3. Cost and Performance – Overview and Indirect Cost


Unit 2015 Cost variation [%]

2025

Trough Tower Trough Tower Trough Tower

Direct EPC costs Mio. $ 675 598 -24 -23 508 459

Engineering, management, add. EPC services

% on direct EPC 5 2

Profit margin and contingencies

% on direct EPC 10 19 6

Indirect EPC cost Mio. $ 101 144 -60 -74 41 37

Project development % on dir.+indir. EPC 10 4

Land cost $ / m² land 1 1

Infrastructure Mio. $ 6 6

Additional owner's cost % on dir.+indir. EPC 3 2

Owner’s cost Mio. $ 112 113 -61 -60 44 46

CAPEX Mio. $ 888 854 -33 -37 593 541

OPEX % of CAPEX 2.2 2.3 2.1 1.9

4. Results – Plant Output and LCOE


Until 2025 LCOEs decrease to

10 $-ct/kWh for medium DNI levels

7 $-ct/kWh for high DNI levels and favourable financing conditions

PPAs ≈ LCOE + 1…1.5 $-ct/kWh

Assuming 4% WACC, LCOE values match well to published PPAs from NOOR

Parabolic Trough 2015 2025

Annual el. output 576 GWh 625 GWh

Overall efficiency 15.1% 17.0%

Solar Tower 2015 2025

Annual el. output 598 GWh 644 GWh

Overall efficiency 15.5% 18.3%

WACC = 7.5%, DNI 2000-2900

PPA NOOR

WACC = 4% DNI 2550

( DNI values in [kWh / (m²∙a)] )

5. Conclusion


CAPEX: 5600 3600 $/kW (-35%) for both technologies (7.5/9h storage)

LCOEs can reach 7 $-ct/kWh (high DNI, favourable financing)

Major cost drivers Trough:

Molten salt as HTF

Trough collector CAPEX

Major cost drivers Tower

Steep learning curve, reduction of contingencies, overcoming of teething troubles

Heliostat field CAPEX

Financing conditions are a massive cost driver:

For each 1%-point WACC reduction LCOEs decrease by 1.1 $-ct/kWh

IRENA publication (2016): „The power to change – Solar and Wind Cost Reduction Potential to 2025”


THANK YOU

for your attention!

Simon Dieckmann

DLR – Line Focus Systems

[email protected]

Contact:

MANY THANKS

to all contributing

partners, co-authors

and colleagues!

mailto:[email protected]

Documents

LCOE reduction potential of parabolic trough and solar tower CSP … SolarPACES... · 2016. 12. 1. · Technology-based bottom-up approach relying on inhouse expertise as well as